Tanker truck manifold level measurement systems and methods

ABSTRACT

A tanker truck offloading system and method. The tanker truck offloading system includes a manifold in fluid communication with a tank and a plurality of tanker truck offloading stations, a tanker truck coupling at an open end of the manifold at each of the plurality of tanker truck offloading stations, and an air separator in fluid communication with the manifold.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. Utility patentapplication Ser. No. 17/024,673, filed Sep. 17, 2020, which claimspriority to U.S. Provisional Patent Application No. 63/022,351, filedMay 8, 2020. The present application also claims priority to U.S.Provisional Patent Application No. 62/978,015, filed Feb. 18, 2020, andU.S. Provisional Patent Application No. 63/034,945, filed Jun. 4, 2020.All of the aforementioned applications are incorporated herein in theirentireties.

BACKGROUND Field of the Disclosure

The present disclosure relates generally to tanker truck fluid transportsystems and methods. The systems and methods may include managementcapabilities related to tank filling and draining and transport offluids.

Description of the Related Art

Significant amounts of time are consumed in hauling and transferringfluids to and from sites for certain activities. For example, hydraulicfracturing operations often require large quantities of water-basedfluid to facilitate hydraulic fracturing and that fluid is often hauledto the hydraulic fracturing sites by tanker trucks. There is furthermoreusually a significant amount of time involved in offloading each tankertruck.

In many current tanker truck operations, tanker trucks offload fluidfrom their tanks using onboard pumps or by pressurizing their tanks tomove the fluid out of each tank. Offloading in those conventionalmanners may take 30 minutes or more and may be limited by the size ofthe discharge piping on the truck, such that increasing the speed ofoffloading can only be minimally impacted by increasing the size of theonboard pump or the pressure applied to the tank. Accordingly, it wouldbe beneficial to have a uniquely configured manifold system forunloading multiple tanker trucks simultaneously that doesn't suffercavitation issues or extended unloading time issues.

For at least the foregoing reasons, it would be desirable to have animproved tanker truck tank unloading system.

It would be advantageous to have an air and gas removal system in afluid offloading system.

It would also be desirable to have a multi-truck simultaneous unloadingsystem.

It would be desirable to have a multi-truck simultaneous loading system,as well.

It would also be advantageous to include fluid transfer managementcapabilities in a tank truck unloading system.

In addition, it would be advantageous to identify the location of atanker truck that is filling or draining.

It would also be advantageous to have a user interface to receiveinformation from the tanker truck unloading system discussed herein.

It would be beneficial to automatically shut off flow during theunloading process when the tanker truck is empty.

It would be advantageous to have an RFID truck related system thatinteracts with the unloading system to transfer pertinent truckinformation and automatically starts the system.

A measurement system that controls an amount of pressure applied to anunloading tank based on the level of fluid in the tank or the volume offluid in the tank would also be beneficial.

It would be advantageous to eliminate cavitation and pump damage onsystems with multiple unloading stations connected to a common manifoldwith a common pump.

It would be advantageous to unload the truck quicker than what ispresently available.

It would be advantageous to track the unloading process via a PLC orcomputer based system control and monitoring system.

It would be advantageous to have redundancy in the system in casefailures occur.

Accordingly, the present invention provides solutions to theshortcomings of prior tanker truck filling and draining systems,apparatuses, and methods. Those of ordinary skill in the art willreadily appreciate, therefore, that those and other details, features,and advantages of the present invention will become further apparent inthe following detailed description of the preferred embodiments of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of thisdisclosure, and the manner of attaining them, will become more apparentand the disclosure itself will be better understood by reference to thefollowing descriptions of embodiments of the disclosure taken inconjunction with the accompanying drawings, wherein:

FIG. 1 is a simplified view of a tanker truck fluid level measurementsystem with location sensing and fluid transfer management capabilities,in accordance with one embodiment of the disclosed invention;

FIG. 2 illustrates an embodiment of a processor-based device to performaspects of the methods and systems disclosed herein;

FIG. 3 is a strap chart correlating fluid level and fluid volume for atanker truck, such as the tanker truck illustrated in FIG. 1 ;

FIG. 4 illustrates an embodiment of a tanker truck fluid levelmeasurement system with management capabilities that includes a tankfill indicator package;

FIG. 5 illustrates a method of performing volume measurement;

FIG. 6 illustrates an embodiment of a vacuum tank unloading system;

FIG. 7 illustrates an embodiment of a manifold control system;

FIG. 8 illustrates a method of operating one or more offloading stationsin a vacuum tank unloading system; and

FIG. 9 illustrates a method of operating an air removal system.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate exemplary aspects of the disclosure, and suchexemplifications are not to be construed as limiting the scope of thedisclosure in any manner.

SUMMARY OF THE INVENTION

In an embodiment, a tanker truck offloading system includes a pluralityof tanker truck offloading stations for a plurality of tanker trucks tooffload fluid into a manifold simultaneously and a gas separation systemcoupled to the manifold. The gas separation system includes anintermediate tank coupled to the manifold, a blower coupled to theintermediate tank to remove air and airborne particles from the fluid,and a pump coupled to the intermediate tank to remove fluid from theintermediate tank. The tanker truck offloading system also includes astorage chamber into which fluid pumped from the intermediate tank bythe pump is deposited.

In another embodiment, a tanker truck manifold system includes amanifold in fluid communication with a tank and a plurality of tankertruck offloading stations, a tanker truck coupling at an open end of themanifold at each of the plurality of tanker truck offloading stations,and an air separator in fluid communication with the manifold.

A method of offloading a tanker truck is also provided. That methodincludes detecting a tanker truck in at least one of a plurality ofoffloading stations, energizing a blower having an inlet duct coupled toa tank receiving fluid from the plurality of offloading stations, theblower to draw gasses from the tank when at least one tanker truck isoffloading at at least one of the plurality of offloading stations,de-energizing the blower when no tanker truck is offloading at any ofthe plurality of offloading stations, energizing a pump having an inletcoupled to the tank when the tank level is above a predetermined highlevel, and de-energizing the pump when the tank level is below apredetermined low level.

Other embodiments, which may include one or more portions of theaforementioned apparatuses and methods or other parts or elements, arealso contemplated, and may have a broader or different scope than theaforementioned apparatuses and methods. Thus, the embodiments in thisSummary of the Invention are mere examples, and are not intended tolimit or define the scope of the invention or claims.

DETAILED DESCRIPTION

The following description is provided to enable those skilled in the artto make and use the described embodiments contemplated for carrying outthe concept. Various modifications, equivalents, variations, andalternatives, however, will remain readily apparent to those skilled inthe art. Any and all such modifications, variations, equivalents, andalternatives are intended to fall within the spirit and scope of thepresent concept.

For purposes of the description hereinafter, the terms “upper,” “lower,”“right,” “left,” “vertical,” “horizontal,” “top,” “bottom,” “lateral,”“longitudinal,” and derivatives thereof shall relate to the concept asit is oriented in the drawing figures. However, it is to be understoodthat the concept may assume various alternative variations, except whereexpressly specified to the contrary. It is also to be understood thatthe specific devices illustrated in the attached drawings, and describedin the following specification, are simply exemplary embodiments of theconcept. Hence, specific dimensions and other physical characteristicsrelated to the embodiments disclosed herein are not to be considered aslimiting.

As employed herein, the term “number” shall mean one or an integergreater than one (e.g., a plurality).

Any reference in the specification to “one embodiment,” “a certainembodiment,” or a similar reference to an embodiment is intended toindicate that a particular feature, structure or characteristicdescribed in connection with the embodiment is included in at least oneembodiment of the invention. The appearances of such terms in variousplaces in the specification do not necessarily all refer to the sameembodiment. References to “or” are furthermore intended as inclusive, so“or” may indicate one or another of the ored terms or more than one oredterm.

FIG. 1 illustrates a tanker truck fluid level measurement system 2 withmanagement capabilities, in accordance with one non-limiting embodimentof the disclosed tank management system. The tanker truck fluid levelmeasurement system 2 includes a tanker truck 10 having a tank 12 and alevel sensor 30 mounted adjacent to the tank. A processor-based device20 communicates with the level sensor 30. The processor-based device 20may be coupled to the level sensor 30 by wires or wirelessly. The truck10 in this embodiment also includes a global positioning device 40,which may determine the relationship of the truck 10 to various gas oroil sites or drill pads 46 and 48, possibly using geofencing technology42 and 44 arranged to identify those sites 46 and 48.

The processor-based device 20 may be a general-purpose computer; atablet; a mobile smartphone, referred to herein as a phone; anapplication specific user interface device; or another device that canbe used to transfer information to the tanker truck fluid levelmeasurement system 2 or receive information from the tanker truck fluidlevel measurement system 2.

The level sensor 30 may be any desired level measuring device,including, for example, a radar level sensor discussed herein, a floattype level sensor, a capacitive type level sensor, a sensor thatconverts pressure into level, or any other type of sensor desired. Thelevel sensor 30 may be mounted adjacent to the tank, for example a radarsensor mounted in or near the top or the tank 12, a pressure sensormounted in the bottom of the tank, or a float sensor mounted in a tubein fluid communication with the tank 12. Moreover, the level sensor 30may be permanently attached to the tank 12 or may be removable from thetank 12 for use on another tank 12 or reuse on the same tank 12 atanother time.

In an embodiment, the level sensor 30, is a radar-based device and ismounted inside the tank 12 near the top of the tank 12. The radar levelmeasuring device may have an accuracy of 2 mm or 0.08″, and may bemounted internally near the top and near the center of the tank 12. Sucha radar device may utilize 80 GHz radar, so that the radar device issmall, compact, and light (possibly approximately 1.4 lbs.). The radardevice may be center mounted underneath a main hatch of the tank 12 forprotection. The radar device may point down into the tank 12 and shoot aradar beam to measure the liquid level height. The radar device may beadvantageous because it may be extremely accurate in terms of providingthe level of the liquid height in the tank 12.

FIG. 2 illustrates an embodiment of the processor-based device 20. Inthat embodiment, the processor-based device 20 includes a processor 212and a communication device 214. The processor 20 and communicationdevice 214 can be combined in a microprocessor or other device and othercomponents (e.g., 220 and 236) may also be included in such amicroprocessor or other device.

The communication device 214 may be wired to a device to which itcommunicates; the communication device 214 may wirelessly communicatewith one or more other devices over a network 240; which may be awireless network, such as a mobile smartphone network; and thecommunication device 214 may operate both wired and wirelessly. Theprocessor-based device 20 may furthermore include memory 220, an input224 that may receive an input signal, such as a signal transmitted by asensor, and an output 226 that may transmit a control signal,instruction, or data to another device, such as a valve actuator orother controlled device. The output device may alternatively or inaddition provide a reading, for example a current volume of fluid in thetank 12, which may be mounted on or near a tank 12 that is being loadedor unloaded.

The processor-based device 20 may also be coupled to a user interface218 to receive one or more signals from, for example, one or more of akeyboard, touch screen 222, mouse, microphone or other input device ortechnology and may have associated software. The user interface may alsotransmit information to, for example, a printer or screen 222 coupled tothe user interface 218 or the output 226.

The memory 220 may, for example, include random-access memory (RAM),flash RAM, dynamic RAM, or read only memory (ROM) (e.g., programmableROM, erasable programmable ROM, or electronically erasable programmableROM) and may store computer program instructions and information. Inembodiments, the memory 220 may be partitioned into sections includingan operating system partition 232 where system operating instructionsare stored, and a data partition 239 in which data, such as one or morestrap charts 300 is stored.

The storage device 236 may include a memory device or a data storagedevice or a combination of both memory and data storage devices, oranother device or devices for storage of data. The data storage 236 maybe considered local storage when the data is stored directly on theprocessor-based device 20 or the data may be accessible to theprocessor-based device 20 over a wired or a wireless network. Thestorage device 236 may furthermore include a computer readable storagemedium that includes code executable by the processor 212 of the tankertruck fluid level measurement system 2 that causes the processor 212 to,at least in part, perform as disclosed herein.

In an embodiment, the storage for the processor-based device 20 mayinclude a combination of flash storage and RAM. The storage may includea computer readable storage medium and may include code executable bythe processor 212.

In an embodiment, the elements, including the processor 212,communication adaptor 218, memory 220, input device 224, output device226, and data storage device 236 may communicate by way of one or morecommunication busses 230. Those busses 230 may include, for example, asystem bus or a peripheral component interface bus.

The processor 212 may be any desired processor and may be a part of acontroller 16, such as a microcontroller, may be part of or incorporatedinto another device, or may be a separate device. The processor 212 may,for example, be an Intel® manufactured processor or another processormanufactured by, for example, AMD®, DEC®, or Oracle®. The processor 212may furthermore execute the program instructions and process the datastored in the memory 220. In one embodiment, the instructions are storedin the memory 220 in a compressed or encrypted format. As used hereinthe phrase, “executed by a processor,” is intended to encompassinstructions stored in a compressed or encrypted format, as well asinstructions that may be compiled or installed by an installer beforebeing executed by the processor 212.

The data storage device 236 may be, for example, non-volatile batterybacked static random-access memory (RAM), a magnetic disk (e.g., harddrive), optical disk (e.g., CD-ROM) or any other device or signal thatcan store digital information. The data storage device 236 mayfurthermore have an associated real-time clock, which may be associatedwith the data storage device 236 directly or through the processor 212.The real-time clock may trigger data from the data storage device 236 tobe sent to the processor 212, for example, when the processor 212 pollsthe data storage device 236. Data from the data storage device 236 thatis to be sent across the network 240 through the processor 212 may besent in the form of messages in packets if desired. Those messages mayfurthermore be queued in or by the processor 212.

The communication adaptor 218 permits communication between theprocessor-based device 20 and other nodes, such as a tanker truckcontroller 35, which may be associated with the level sensor 30, or aremote monitoring peripheral computer 37 or server, both illustrated inFIG. 4 . The communication adaptor 218 may be a network interface thattransfers information from a node such as a networked device, whichwould include an actuating device such as valve 60 or a sensing device,such as level sensor 30, the tanker truck controller 35, the remotemonitoring peripheral computer 37, a general purpose computer (notillustrated), a user interface device, such as the processor-baseddevice 20 depicted in FIGS. 1 and 2 , or another node. The communicationadaptor 218 may be an Ethernet adaptor or another adaptor for anothertype of network communication. It will be recognized that theprocessor-based device 20 may alternately or in addition be coupleddirectly to one or more other devices through one or more input/outputadaptors (not shown).

The processor 212 may contain in its memory 220 or data storage device226, or may communicate with another node or data storage device toaccess, a plurality of strap charts 300, an example of which isillustrated in FIG. 3 . The strap charts 300 may equate the level offluid in a tank 12 to the volume of fluid in that tank 12, establishinga simple and accurate way to determine the volume of fluid in a tank 12.A separate strap 330 chart may exist for each of a variety of tanks 12from which the processor-based device 210 receives information. Forexample, a first tanker truck 10 may include a tank 12 and a uniqueidentifier may be associated with that tank 12 or the truck 10 on whichthe tank 10 is situated.

The tank identifier may be any unique identifier of the tank 12 or thetruck 10 on which a particular tank 12 is mounted and may be recognizedin a variety of ways. For example, a user interface may be used toidentify the tank currently in position to operate (e.g., load orunload), a unique identifier may be transmitted by the tank 12 orassociated truck 10 by any signal transmitting device, or an identifiermay be read and transmitted by a geofencing 42, 44 or other positiondetermination device that senses the presence of the tank 12 or itsassociated truck 10.

Because of the variances that may occur through manufacturing, use, anddamage, for example, to each tank 12 on each truck 10, the volume of avariety of tanks 12, potentially every tank 12 encountered by theprocessor-based device 20, at various levels, may be desired to bedetermined. To provide the volume of the liquid in the tank 12, eachtank 12 may be separately calibrated. Such calibration may use acalibration pump skid and each calibration pump skid may utilize aflowmeter 62 (illustrated in FIG. 4 ) to measure an amount of fluidplaced in the tank 12. The amount of fluid placed in the tank 12 may beassociated with a level of the fluid in the tank 12 to create a strapchart 220 for that tank that provides the volume of fluid in the tank 12as an output to a user or device when the level of fluid in the tank isprovided as an input by a user or device. For example, in oneembodiment, the level of the fluid may be measured each time a barrel offluid is placed in the tank 12 and the volume of fluid that has beenplaced in the tank 12 may be associated with the current fluid level inthe tank 12 in a table or strap chart 300 so that the number of barrelsof fluid in the tank 12 may thereafter be determined by reading from thestrap chart 300 the volume that corresponds to any fluid level measuredin the tank 12.

In one embodiment, the flowmeter 62 may be a National Institute ofStandards and Technology (NIST) certified calibrated flowmeter that iscalibrated to be accurate to 0.02%. That flowmeter 62 may be employed toachieve an accuracy of + or − less than 10 gallons and may be accurateto 1 gallon in a nominal 110 bbl tank. The strap chart 300 may beestablished in the processor-based device 20 in the form of atwo-dimensional array or other database format. The calibrated accuracyof the combined flow meter 62 and strap chart 300 can be correlated tothe overall accuracy of the level system, creating a calibrated levelsystem by proxy.

It may furthermore be noted that water may, for example, be placed inthe tank 12 to create the strap chart 330, but any liquid or liquifiedmixture may thereafter be placed in the tank 12 and the volume of thatliquid in the tank 12 may be measured using a level sensor 30 and thestrap chart 300 for that tank 12. Fluids that may be measured in thetank 12 using the disclosed system may include, but are not limited to,oil, gasoline, water, milk, water mixed with various other solids andliquids, or any other fluid or other substance that may be transportedvia a tank.

The custom calibrating pump skid disclosed herein may be used whenfilling the tank 12 during a calibration phase. At the same time thetank 12 is being filled, the radar or other level measuring device 30will measure the liquid level in the tank 12 and the processor-baseddevice 20 can develop a custom strap chart 300 for the tank 12 as theliquid is placed into the tank 12.

FIG. 3 illustrates a level vs. volume table 300, also called a strapchart, for a particular tank 12. The strap chart 300 may thereafter beused for level/volume correspondence for that tank 12 for the life ofthat tank 12 or until a modification is made to that tank 12. Similarly,other tanks 12 could be calibrated on the pump skid and have customstrap charts 300 attached to them for use throughout the life of thosetanks 12. Accordingly, in the future, when the level device 30 reads theliquid level, it may compare the level sensed to the custom strap chart300 for that tank 12 and identify the exact volume of liquid in the tank12 from the level of the fluid in that tank 12. In that way, variationsin tank manufacturing are advantageously irrelevant due to use of thecustom strap chart 300 developed for each tank 12. Furthermore, the tankcalibration is performed independent of the type of liquid in the tank12, as chemical composition does not impact the readings or volume.

In an embodiment, a plurality of strap charts 300 is accessible by theprocessor-based device 20, one strap chart 300 existing for every tank12 in which fluid volume is to be measured. Each strap chart 300correlates a level of fluid in a particular tank 12 to a volume of fluidheld by that tank 12 at that level.

FIG. 4 illustrates another embodiment of a tanker truck volumemonitoring system 402. The tanker truck fluid level measurement system402 includes a tanker truck 10 having a tank 12, a transfer hose 64 thatcan carry fluid either to the tank 12 or away from the tank 12, aprocessor-based device 20, a level sensor 30, an indicator 40, abreather valve 50, and a fluid valve 60. The volume monitoring system ofFIG. 4 includes an indicator package to assist an operator in fillingthe tank 12. In one embodiment, the system 402 contains an indicatorpackage that includes two indicator lights. The first light on theindicator 40 may illuminate when the tank 12 is almost full (e.g., 5barrels less than full) and the second light on the indicator 40 mayilluminate when the tank 12 is full or very nearly full. The first lighton the indicator 40 may, for example, be yellow and may be used todirect the operator to close a valve on a production tank from which thefluid is being pumped or otherwise transferred into the tank 12 of thetruck 10. After stopping the flow of fluid from its source, the operatormay empty the transfer hose 64 communicating between the fluid sourceand the tank 12 into the tank 12. For example, the operator may open abreather valve 50 on the tank 12 and drain the transfer hose 64 into thetank 12. The truck 10 may draw a vacuum during tank 12 filling and maycontinue to draw the vacuum when draining the transfer hose 64, therebydraining the fluid from the transfer hose 64 into the tank 12.

The second light on the indicator 40 may illuminate when the tank 12 isfull or very nearly full. The operator may then cease placing fluid inthe tank 12 and shut the production water valve 60 and the breathervalve 50, thus yielding a full tank 12 of fluid. As such, the first andsecond lights on the indicator 40 advantageously assist the driver orother operator to know when to stop filling the tank 12 and shut thevalve 60 on the tank 12 so the truck 10 is filled accurately and fully.Other light functionality may also or alternatively be included toindicate empty status or other important points in the filling oremptying process.

In an embodiment, various color indicator 40 lights turn on at the rearof the truck 10 during the filling operation to assist the driver oroperator. A yellow light illuminates on the indicator 40 on when thetruck is almost full (i.e., 5 bbls to full) and a red light illuminateson the indicator 40 to direct the driver to close the incomingproduction water valve 60. The operator then opens a ½″ breather valve50 on the tank 12 and empties the transfer hose 64 into the tank 12.

A truck tank pressurization system 25 may be provided to providepressure or vacuum to a truck 10 tank 12. The truck tank pressurizationsystem 25 may be contained within the tanker truck and the truck tankpressurization system 25 may be powered by the tanker truck 10.Alternatively, the truck tank pressurization system 25 may be externalto the truck 10, for example at an onloading or offloading site. Thetruck pressurization system 25 may furthermore be powered externally tothe truck, again for example at an onloading or offloading site.

Truck 10 tanks 12 and the vessels they are loading from or unloadinginto may be pressurized to enhance that process, for example, using thetruck tank pressurization system 25. In certain embodiments, when atruck 10 tank 12 is unloading, the tank 12 is pressurized to assist inmoving fluid out of the tank 12. In another embodiment, a vessel thetank 12 is unloading into may create a vacuum or negative pressure toassist in drawing the fluid out of the tank 12. In embodiments where thetank 12 is being loaded, a vessel providing fluid to the tank 12 may bepressurized to assist the fluid in moving from the vessel to the tank 12or the tank 12 may draw a vacuum to assist in moving the fluid from thevessel to the tank 12. In various embodiments, the truck 10 may continueto operate and draw a vacuum until the transfer hose 64 is empty todrain the fluid in the transfer hose 64 into the tank 12. In certainembodiments, the pressure or vacuum may be modified as loading orunloading operations progress, for example, reducing the pressure in atank 12 as the fluid level in the tank 12 is reduced or reducing thevacuum in the tank 12 as the tank fills. For example, pressure providedto a tank 12 during unloading may be reduced when the tank 12 approachesempty to reduce the amount of air missing with the unloading fluid. Ashas been mentioned, the operator may shut the production water valve 60when a tank 12 is filling and full all but the volume of the transferhose 64, pressure and suction may be removed or de-energized at thattime, and once the transfer hose 64 has been emptied into the tank 12,the tank 12 should have a full load of fluid.

In embodiments, the level sensor may be used to adjust the pressure orvacuum applied to the tank 12 or the vessel. For example, when the tank12 is draining, the volume monitoring system 402 may provide a signal toan apparatus pressurizing the tank 12 reducing the pressure applied inthe tank 12 as the level or volume of the tank 12 is reduced. When thetank 12 is filling, the volume monitoring system 402 may provide asignal to an apparatus creating a vacuum in the tank to reduce thevacuum when the tank 12 nears full.

It should be recognized that any number of lights may be included on theindicator 40 to indicate fluid level in the tank 12 and thereby toassist the operator in filling the tank 12. It should furthermore berecognized that indicators 40 other than lights or in addition to lightsmay be employed. For example, an audible indicator may be employed toattract the attention of the operator and warn the operator that thetank 12 is nearing its full fill point. In certain embodiments, acombination of an audible indicator, a light indicator, and possiblyother indicators are included in the system 2 indicator 40 to gain theattention of the operator when the tank is nearly full.

Furthermore, in accordance with the disclosed invention, the productionwater valve 60 may be automated to close-off flow to or from the tank 12at a predetermined time associated with tank 12 level. Accordingly, inan embodiment, the lighting package may operate as describedhereinabove, and the automated valve 60 may automatically close when apre-set tank 12 fill level is reached. Automatic closure of theproduction water valve 60 advantageously prevents the tank 12 fromoverfilling and scrubbing out.

A fill-level other than completely full for a tank 12 can alternativelybe pre-set so that the fill indicator 40 lights illuminate or theproduction water valve 60 closes automatically when that preset level isreached, in embodiments in which a full tank 12 is not desired. Forexample, when the truck 10 is to travel roads that do not permit theweight of a full tank 12 load of fluid, less than a full load in thetank 12 may desirable. One example of when the aforementioned may beapplied advantageously is where a 110 bbl truck is not permitted tocarry 110 bbls of fluid to a particular location, such as a site in Ohiowhere a driver must carry no more than 64 bbls per load due to weightrestrictions. In the past it has been difficult to determine if therewere 64 bbls on the truck, but using the present fluid level measurementsystem, the driver or operator can pre-set 64 bbls to be transferredinto the tank 12 and the indicator 40 lights may illuminate or theautomatic valve 60 may close when the tank 12 load approaches or reaches64 bbls.

Where indicator 40 lights are used in such a less than full loadembodiment, the first light on the indicator 40 may illuminate when thetank 12 is approximately 64 barrels less the volume of the transfer hose64 so the operator or automatic valve control system can stop flowthrough the transfer hose 64 from the fluid source. The operator or mayempty the transfer hose 64 into the truck 10 tank 12 at that time. Thesecond indicator 40 light may illuminate when the tank 12 is filled withthe final 64 barrels of fluid to indicate that the tank 12 is full tothe desired volume. In certain embodiments, the processor 212 may havestored or receive a quantity of fluid held by the transfer hose 64 andmay determine when to indicate that fluid transfer should cease based onthe difference between the capacity of the tank 12 and the capacity ofthe transfer hose 64.

In accordance with the disclosed system, the amount of fluid in the tank12 can advantageously be determined with precision. Once that is known,reports can be generated for invoicing and billing purposes, regulatoryreporting purposes, safety purposes (e.g., if the truck 10 would have anaccident the responders will know exactly how much liquid is in thetruck 10) and other desired purposes.

The level reading may be transmitted to one or more computerized devicesfor processing. For example, the level may be sensed by a level sensor30 and the level may be transmitted electronically to a computerizeddevice, such as the processor-based device 20, that uses the strap chart302 for that tank 12 to determine the volume of fluid contained in thetank 12. In an embodiment, the level sensor 30 is a radar unit and thelevel is wirelessly transmitted via Bluetooth or another form oftransmission to a level gauge located at the rear of the truck 10, alevel gauge in the cab of the truck 10, or to an external userinterface, such as a computer, a phone 20 shown in simplified form inFIG. 1 , a tablet, or another electronic device. The processor-baseddevice 20 may also receive the level from the level sensor 30 andgenerate volume data for the fluid for tracking purposes or otherpurposes. Regulatory reports, Bills of Lading, and other documentationmay be automatically be generated from the processor-based device 20 oranother device based on the information received and determined by thedevice 20 or another device. For example, the volume of water dischargedat a site by each truck that discharged water at that site may beprovided electronically or in printed form by the device 20

Alternatively, or in addition, the level sensor 30 may transmit toanother device, an electronic signal that corresponds to an outputsignal provided by the level sensor 30, such as an electronic signalthat corresponds to a 4-20 mA signal. In an embodiment, a wirelessdevice, such as a Bluetooth device, is enabled to capture a 4-20 mAsignal from a radar-based level sensor 30 or another level sensingdevice. The radar-based level sensor 30 senses the level of the fluid inthe tank 12 and transmits that level to the wireless device via a 4-20mA signal. That signal is then referenced against the calibrated strapchart and the volume of fluid held in the tank 12 is produced, forexample in gallons or barrels, from the level and the strap chart.

It is also contemplated herein that the system 2 may be employed with anumber of geo-fences 200, 300, shown in simplified form in dashed linedrawing in FIG. 1 to determine the location of the truck 10 when itloads or unloads. For example, reference numerals 210, 310 denote wellpads configured to contain oil that the truck 10 will obtain. As shown,surrounding each well pad 210, 310 is a corresponding one of thegeo-fences 200, 300, a virtual fence that may include GPS coordinates ofthe location of the well pads 210, 310. Additionally, as shown, thetruck 10 may also have a GPS system 100, shown in simplified form andthe location of the truck 10 may be determined from the GPS system 100.Using that system, when a truck 10 that arrives at well pad 210, the GPSsystem 100 will indicate that the truck 10 is located at the geo-fence200. Accordingly, when the truck 10 arrives at the geo-fence 200, thegeo-fence 200 will advantageously be able to indicate that the truck 10was previously at, for example, the geo-fence 300. This truck 10location information makes tracking the fluid in the truck 10significantly easier. Once the fluid is moved to a new well pad 210,310, the truck 10 is registered at the new geo-fence 200, 300, which isrecorded for the specific truck. In this manner, the travel path anddistribution or accumulation of the liquid in the tank 12 can berecorded and monitored.

FIG. 5 illustrates a method 500 of measuring the volume of a tankertruck 10 tank 12 performed by a processor 212. At 502, a tank identifierindicates to the processor 212 which tank 12 the level sensor 30 issensing, the level sensor 30 providing a signal corresponding to thelevel of fluid in that identified tank 12. At 504, the level sensor 30provides a signal to the processor 212 corresponding to the level offluid in the identified tank 12 and the processor 212 receives thatlevel signal. At 506, the processor 212 correlates the level of thefluid to a strap chart 300 for the identified tank 12, the strap chart300 having been previously created and stored for access by theprocessor. At 508, the processor 212 provides an output representing thevolume of fluid that corresponds to the level of fluid indicated for thetank 12, the volume correlating to level in the strap chart 300.

FIG. 6 illustrates an embodiment of a vacuum tank unloading system 100.The vacuum tank unloading system 100 of this embodiment may be employedto expedite offloading of tanker trucks 10. In this embodiment aplurality of tanker truck 10 offloading stations 110 are provided sothat more than one tanker truck 10 can have fluid from their associatedtanks 12 offloaded simultaneously into the manifold. For example, in anembodiment for offloading tanks of water-based fluids used in hydraulicfracturing, ten offloading stations 110 may be provided. A tanker truck10 may pull up to and connect to a manifold system 101 through anoffloading station 110 when that offloading station 110 is not occupiedor otherwise used by another truck 10. An offloading station 110 can beused independent of other station occupancy, regardless of any use ormaintenance occurring of the other offloading stations 110, andregardless of whether one or more trucks 10 occupying one or more otherstations are in the process of offloading. The tanker truck 10 thatpulls into an offloading station can connect to an offloading line 112at the offloading station 110 and offload the contents of its tank 12through the offloading line 112 while other trucks 10 are simultaneouslyoffloading their tanks 12.

In an embodiment, an offloading station 110 includes a flexible transferhose hook-up coupling 152 through which fluid from the tank 12 of thetruck 10 can flow into a manifold 114 and from there, directly orindirectly, into a site tank 120. The manifold 114 may be in fluidcommunication with each offloading station 110 and the site tank 120.The manifold 114 may be a piping system that accepts fluid from eachoffloading station 110, combines fluid received from the offloadingstations 110 at one or more junctions 154, and deposits the fluidreceived from the offloading stations 110 into the site tank 120.

The manifold 114 may be configured in various ways that are suited to anoffloading site. The manifold 114 illustrated in FIG. 6 includes aplurality of offloading lines 112, with a manifold 114 branch extendingto each offloading station 110. The offloading lines 112 join at one ormore junctions 154 to a common line 114 that extends to a tank such asthe intermediate tank 162 illustrated in FIG. 6 . A fill line 156extends from the intermediate tank 162 to a destination which, in theembodiment illustrated in FIG. 6 , is the site tank 120. The fill line156 may alternatively extend to any desired destination into which thefluid from the truck 10 tanks 12 is desired to be deposited, including,for example, a storage vessel of any type, an underground storage area,a well, or a rig of some type, such as a drill rig. The manifold 114 mayfurther include a variety of apparatuses in each offloading line 112,which may include an offloading valve 140, a sight tube 142, a pressuregauge or sensor 144, a flow gauge or sensor 146, a temperature gauge orsensor 148, or any other desired gauge or sensor. For the purpose ofthis disclosure, gauges may provide a visual representation of acharacteristic of the fluid in the offloading line 112 or any otherpipe, and a sensor may provide a signal that represents a fluidcharacteristic to a processor-based device, such as the one illustratedand discussed in connection with FIG. 2 or a control system or othercomputing device, such as the manifold control system 402 illustrated inFIG. 7 . Sensor signals may, furthermore, be transmitted through wiresor wirelessly.

A flow meter 150 or other flow measuring device may be placed in themanifold 114 common line to measure the total flow through the manifold114 of the vacuum tank system 101. That flow measurement may be used todetermine total flow into the vacuum tank system 101 and may be used tocontrol flow into the manifold 114, for example, through the offloadingvalves 140. Alternatively, a flow switch may be placed in the manifold114 common line to indicate fluid is flowing through the manifold 114.Either the flow meter 150 or switch may be coupled to a computerizedmonitoring or control system including the processor-based device 20illustrated and discussed in connection with FIG. 2 and the controlsystem 400 illustrated and discussed herein in connection with FIG. 7

The offloading valves 140 may be located in each offloading station 110to control or flow from the offloading stations 110 or to isolate one ormore offloading stations 110. The offloading valves 140 may be a varietyof types of valves, including a ball valve, a gate valve, or a globevalve. The offloading valve 140 may furthermore be actuated manually ormay be automatically controlled for full opening or closure or may bemodulated for regulated flow by a manifold control system, such as thecontrol system 400 illustrated in FIG. 7 . The offloading valve 140 maybe of a size that permits full flow of fluid from the truck 10 tank 12,such as a 4″ valve with a full flow characteristic. The full flowcharacteristic of a ball valve, for example, may be beneficial to enablefast offloading of tanks 12 coupled thereto. Alternatively, theoffloading valve 140 may be configured with a linear controlcharacteristic, such as that provided by a globe valve, or may haveanother desired flow characteristic. The offloading valve mayfurthermore be used to permit flow into the offloading line 112 whenopen and to prevent flow into the offloading line 112 when closed.

Control of the offloading valve 140 and other components of the vacuumtank unloading system 100 may be performed using a computer, such as theprocessor-based device 20 illustrated and discussed herein in connectionwith FIG. 2 , or a controller, such as the manifold control system 400illustrated and discussed herein in connection with FIG. 7 .

The pressurization or vacuum system discussed in connection with FIG. 4herein may be used in operation of embodiments of the pressurize orvacuum in the vacuum tank unloading system 101. For example, the vacuumtank unloading system 101 may be used in one or more trucks 10 that areunloading to pressurize the tanks 12 of those one or more trucks 10 whenunloading those tanks into the offloading lines 112 and manifold 114.Alternatively or in addition, vacuum may be applied to the intermediatetank 162 or another place in the offloading lines 112 and manifold 114to draw fluid from offloading tanker trucks 10 into the vacuum tankunloading system 101. That vacuum may be applied by the air removalsystem 160 or may be provided by a separate vacuum apparatus.

The truck fluid level measurement system 20 may be used to transmit oneor more truck tank levels to the vacuum tank unloading system 100. Thetruck tank level information may be used by the processor-based device,such as the one illustrated and discussed in connection with FIG. 2 or acontrol system or other computing device, such as the manifold controlsystem 402 illustrated in FIG. 7 , to automatically control the vacuumsystem to decrease the vacuum as the fluid level in the truck 10 tank 12or tanks 12 decreases to minimize air mixing with the fluid.

Fluid unloaded from a tanker truck 10 is known to sometimes encountergas, particularly air, mixing with the fluid. It is common, for example,for an offloading tank to provide nearly all fluid when it begins tooffload and to provide fluid mixed with a substantial amount of air whenthe tank 12 is nearly empty. Thus, in one example, multiple trucks 10unload simultaneously and during that simultaneous offloading sometrucks 10 may provide nearly pure fluid with little air while othertrucks 10, for example those with tanks that are nearly empty oroffloaded, provide fluid mixed with air or simply air with little fluid.When gasses, such as air, are mixed with the fluid, the gas pockets inthe fluid tend to cavitate and can, for example, airlock a non-floodedsuction water pump. Such airlock inhibits operation of the pump and cancause damage to the pump. Accordingly, an air removal system 160 may beprovided in the vacuum tank system 100.

The air removal system 160 of the vacuum tank system 101 may include anintermediate tank 162 coupled to a blower 164 for air removal and a pump166 to transfer fluid from the intermediate tank 162 to the site tank120. A benefit of including such an air removal system 160 is that fluidreaches the pump 166 and is moved by the pump into the site tank 120,while air is removed from the intermediate tank 162 by the blower 164,preventing air or other gasses in the intermediate tank 162, likelysourced from the offloading trucks 10, from reaching the pump 166.Another benefit of including an air removal system 160 is the truck 10tanks 12 may offload more quickly with the pump 166 drawing fluid fromthe vacuum tank system 100 and the blower 164 applying a vacuum to theintermediate tank 162.

The blower 164 portion of the air removal system 160 may include a foamtank 170 into which foam and air may transfer from the intermediate tank162 through gravity or vacuum created by the blower 164 or another fanor air moving device. The blower 164 portion of the air removal system160 may also include a suction valve 172, which may be operatedautomatically or manually, and a silencer 174 to reduce noise emittedfrom the blower 164 of the air removal system 160. The air removalsystem 160 may also include a drain line 178 through which fluids thatpass through the blower or otherwise collect in the blower 164 dischargeto drain into the site tank 120. The blower 164 may furthermore maintaina vacuum in the upper portion of the intermediate tank 162 to assist inremoving air, foam or other airborne particles from the intermediatetank 162. The vacuum created by the blower 164 may furthermore drawfluid into the intermediate tank 162.

The suction valve 172 may be opened, closed, or modulated, for exampleby the processor-based device 20 illustrated and discussed herein inconnection with FIG. 2 , or the manifold control system 400 illustratedand discussed herein in connection with FIG. 7 . The suction valve 172may be opened or closed to control suction applied by the blower 164 tothe intermediate tank 162 or the manifold 114 or to separate fluidcommunication between the blower 164 and the intermediate tank 162, forexample for maintenance.

The blower 164 may, moreover, have a variable speed motor such that apressure sensor may be placed in the upper part of the intermediate tank162 and the blower speed may be varied to maintain a desired amount ofvacuum at that pressure sensor through the manifold control system 400.In certain embodiments, the blower 164 will be de-energized if the fluidlevel in the intermediate tank 162 rises to a level that may cause fluidto be drawn into the blower 164.

The pump 166 portion of the air removal system 160 may include a sighttube 142, a pressure gauge or sensor 144, a flow gauge or sensor 146, atemperature gauge or sensor 148, or any other desired gauge or sensorsituated in piping before or after the pump 166. The pump 166 portion ofthe air removal system 160 may also include a suction valve 176 that maybe manually or automatically operated to control fluid flow or toprevent fluid communication between the intermediate tank 162 and thepump 166, for example, for maintenance.

In an embodiment, the pump 166 will operate automatically to maintain adesired fluid level in the intermediate tank 162. In such an embodimenta high-level switch 182 may energize the pump 166 to transfer fluid fromthe intermediate tank 162 to the site tank 120 when the high level seton the high-level switch 182 is exceeded and a low-level switch 184 mayde-energize the pump 166 to allow fluid to gather in the intermediatetank 162 when the level of the intermediate tank 162 as set on thelow-level switch 184 is reduced below the level sensed by the low-levelsensor switch 184. A level sensor may replace both the high-level switch182 and low-level switch 184 in certain embodiments, the level sensorenergizing and de-energizing the pump 166 at desired levels. Ahysteresis band may be set between the high-level switch and thelow-level switch to minimize pump cycling. In another embodiment, thepump 166 may have a variable speed motor and may vary the speed of themotor to maintain a desired level in the intermediate tank 162.

The intermediate tank 162 may, for example, be a 4000-gallon tank and itmay be maintained at a vacuum when the vacuum tank system 101 isoperating. The vacuum may speed offloading by drawing fluid from thetruck 10 tanks 12. Air and other gasses may be separated from the fluidin the intermediate tank 162 when the bower 164 and pump 166 operate asdescribed in connection with the air removal system 160 and pump 166described herein.

The vacuum tank system 101 may be placed in a heated building or trailerto prevent freezing and drains may be installed in the manifold 114 todrain the manifold 114 when, for example, the manifold 114 is not in useor winterization is required.

FIG. 7 illustrates an embodiment of a manifold control system 400. Themanifold control system 400 may include a computerized monitoring and/orcontrol system (CMCS) controller 402, such as, for example, aprogrammable logic controller (PLC) with inputs 404 and outputs 406 or adistributed wireless control system. The manifold control system mayinclude any or all of the components discussed in connection with theprocessor-based device 20 described herein including, but not limitedto, a processor 212, memory, 220, and a data storage device 236. Inputs404 to the controller 402 may include inputs configured to receivesignals transmitted from one or more sensors such as, for example,pressure sensors, flow sensors, and position sensors. Outputs 406 fromthe manifold control system 400 may include outputs configured totransmit control signals and actuating signals such as, for example, a4-20 mA control signal sent to a variable speed pump or blower VFDdrive, relays to energize and de-energize equipment such as theoffloading valves 140, other electrical signals, and 2-position ormodulating pneumatic and hydraulic signals to be transmitted to variousvalves or other equipment.

FIG. 8 is a flow chart of a method 520 of operating one or moreoffloading stations 110 in a vacuum tank unloading system 100 that maybe performed, at least in part, by the controller 402 or distributedcontrol system. In the embodiment illustrated in FIG. 8 , the controller402 or distributed control system may receive a signal at an input 404from a sensor indicating that a tanker truck 10 is located in anoffloading station 110 at 522. The controller 402 or distributed controlsystem may alternatively or in addition receive a signal at an input 404that identifies the truck 10 that is positioned in that offloadingstation 110 at 524. At 526, the controller 402 or distributed controlsystem may receive an input 404 indicating that at least one truck 10 inan offloading station 110 is connected to the hook-up and ready tounload the contents of its tank 12. In embodiments, the controller 402or distributed control system may receive the identification of thetruck 10 unloading by methods including a user inputting thatinformation or the truck 10 transmitting an identifier. At 528, thecontroller 402 or distributed control system may open or otherwisecontrol fluid flow from the tanker truck 10, through the offloadingstation 110 using the offloading valve 140. Fluid flow through theoffloading valve may be controlled in various ways including to maintaina desired pressure at pressure sensor 144 or to maintain a desired fluidflow rate at the flow meter 150.

In embodiments, the method 520 operates to unload one or more tankertrucks 10 into a manifold, thereby more quickly offloading fluid carriedby those tanker trucks 10 than traditional offloading. In doing so, atanker truck 10 may pull into an offloading station 110 and connect thetanker truck 10 tank 12 to the manifold 114 through a flexible transferhose hook-up coupling 152. A transfer hose may be connected between thetanker truck 10 tank 12 and a transfer hose hook-up coupling 152 influid communication with the manifold 114 to permit fluid flow from thetank 12 into the manifold 114.

FIG. 9 is a flow chart of a method 550 of operating an air removalsystem 160 in a vacuum tank unloading system 100 that may be performed,at least in part, by the controller 402 or distributed control system.At 552, in response to a signal indicating there is fluid flowing intothe manifold 114, the controller 402 or distributed control system mayoperate the air removal system 160, energizing the air removal blower164 to remove air from incoming fluid entering the intermediate tank 162or to provide suction to more quickly empty fluid from offloading truck10 tanks 12. Sensing that there is fluid flowing into the manifold maybe performed in a variety of ways, including: sensing that a transferhose has been connected to the manifold 114 at one of the offloadingstations 110, sensing that an offloading valve 140 has been opened,sensing fluid flow in the manifold 114 The method of operating an airremoval system 550 may also open or otherwise control the opening of thesuction valve 172 to permit airflow to and through the blower 164. Inembodiments wherein the blower 164 is operated by a variable speeddrive, the controller 402 or distributed control system may control thespeed at which the blower 164 operates, for example, to maintain adesired vacuum at a pressure sensor 180 in the intermediate tank 162 oranother desired location.

At 554, the controller 402 or distributed control system may control thepump 166. In embodiments, the pump 166 may be cycled on and off inresponse to high and low-level switches 182 and 184 or a level sensor tomaintain a desired fluid level in the intermediate tank 162.Alternatively, the speed of the pump 166 may be varied to maintain adesired level in the intermediate tank 162 in embodiments where avariable speed pump 166 is employed.

At 556, the controller 402 or distributed control system may de-energizethe blower 164 and pump 166 when fluid is no longer flowing through themanifold 114 and the intermediate tank is at a desired level.

The inputs 404 of the controller 402 or distributed control system mayinclude statuses 412 and 414 for various valves, such as offload station110 valves 140, air removal system 160 isolation valves, or a site tank120 isolation valve. The inputs may also include level sensors orswitches, such as high and low site tank 120 level switches orintermediate tank 162 level switches.

The controller 402 or distributed control system outputs 406 may includecontrol relays or other mechanisms to energize and de-energizecomponents of the vacuum tank system 100, such as one or more valves,including offloading valves 140 and isolation valves; pumps includingpump 166; the blower 164; or any other component of the vacuum tanksystem 100 that is desired to be operated automatically.

The controller 402 or distributed control system may control its outputs406 in accordance with the information sensed at its inputs 404, forexample, energizing the pump 166 when the site tank 120 reaches a lowlevel, as sensed by a site tank low level switch or level sensor. Thecontroller 402 or distributed control system may also perform one ormore functional checks when the vacuum tank system 100 is energized.Where the controller 402 or distributed control system performsfunctional checks, it may automatically energize the pump 166 and blower164, open valves including offload station 110 valves 140, air removalsystem 160 isolation valves, or a site tank 120 isolation valve and maymonitor the truck 10 tank 12 offloading process through attached sensorsas discussed herein.

The controller 402 or distributed control system may also communicateinformation it contains through wires or wirelessly, for exampleproviding vacuum tank system 100 status and operational parameters to auser interface and receiving override commands or modified operationalrules from the user interface.

An objective of the vacuum tank system 100, is to unload fluid fromtanker trucks 10 in a short amount of time and the per-truck offloadingtime of such a system 100 is expected to be one-quarter of theoffloading time required for conventional offloading.

Another aspect of the current invention is creation of a device thatreceives a 4-20 ma signal from a sensor and transmits that 4-20 masignal to another device through wires or wirelessly, for example by wayof Bluetooth technology.

While this disclosure has been described as having exemplary designs,the present disclosure can be further modified within the spirit andscope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the disclosure using itsgeneral principles. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this disclosure pertains and which fallwithin the limits of the appended claims.

What is claimed is:
 1. A tanker truck offloading system comprising: amanifold; a plurality of tanker truck liquid offloading stations for aplurality of tanker trucks having liquid laden tanks to offload theliquid from the tanks into the manifold simultaneously; a gas separationsystem coupled to the manifold, the gas separation system including: anintermediate tank coupled to the manifold; a blower coupled to theintermediate tank to remove air and airborne particles from the liquid;and a pump coupled to the intermediate tank to remove liquid from theintermediate tank; and a storage chamber into which liquid pumped fromthe intermediate tank by the pump is deposited.
 2. The tanker truckoffloading system of claim 1 further comprising a tanker truckoffloading monitoring system having a sensor coupled to at least one ofthe offloading stations and the manifold.
 3. The tanker truck offloadingsystem of claim 2, wherein the tanker truck offloading monitoring systemfurther controls a function of the tanker truck offloading system. 4.The tanker truck offloading system of claim 2, wherein the offloadingmonitoring system includes a processor, the processor includinginstructions that, when executed by the processor, cause the processorto: receive a signal from a sensor indicating when a truck is in one ofthe plurality of offloading stations; and receive informationidentifying the truck in one of the plurality of offloading stations. 5.The tanker truck offloading system of claim 4, wherein the processorfurther contains instructions that, when executed by the processor,cause the processor to open an offloading valve associated with theoffloading station occupied by the truck.
 6. The tanker truck offloadingsystem of claim 5, wherein the processor opens the offloading valveassociated with the occupied offloading station after the processorreceives an indication that a transfer hose is coupled to the offloadingstation.
 7. The tanker truck offloading system of claim 2, wherein theoffloading monitoring system includes a processor, the processorincluding instructions that, when executed by the processor, cause theprocessor to: receive a signal from a sensor indicating that there isfluid flowing in the manifold; energize a blower drawing gas from theintermediate tank when fluid is flowing in the manifold; energize a pumpdrawing fluid from the intermediate tank when a fluid level in theintermediate tank exceeds a high limit predetermined level; andde-energize the pump drawing fluid from the intermediate tank when thefluid level in the intermediate tank is less than a low limitpredetermined level.
 8. The tanker truck offloading system of claim 7,wherein the processor further contains instructions that: cause a firstvalve to open allowing fluid to flow through the pump from theintermediate tank; and cause one of a second valve and a damper to openallowing gas to flow through the blower from the intermediate tank. 9.The tanker truck offloading system of claim 2, wherein the gasseparation system removes air and airborne particles from theintermediate tank.